Among dynamo-electric machines conventionally provided is a dynamo-electric machine including a salient pole rotor structure. In such a salient pole rotor structure, multiple protrusions protruding radially outward are arranged at the outer circumferential portion of the magnetic pole core constituting the center portion of the rotor, along the circumferential direction, and a field winding is wound around each protrusion.
In this case, provided on the top surface of the protrusion is a magnetic pole head, which is adapted to restrain the field winding wound around the protrusion. This prevents the field winding from deviating from the protrusion due to centrifugal force by the rotation of the rotor.
Conventional dynamo-electric machines as described above are disclosed, for example, in Patent Documents 1 and 2.